OK, I’m not sure that title is clear and that might be why I’ve not managed to find a previous discussion on this by searching. If it has been discussed before my apologies, please point me in the direction of thread.

What I am trying to do is plot file handlers case loads over a period of times. I have a list of cases with the references, the file handler, the date it was allocated and the date it was concluded (if it is not still active.) So my x-axis is date, say at week level, and for each week I want the count of cases where the date allocated <= that week and the date concluded is null or > that week. Can anyone think of a way to do this?

I’ve produced some dummy data to work with but I haven’t built anything in the attached packaged workbook because I’m not sure how to begin!

Thanks for you response Joe. Your suggestion works but using an inner join creates a huge data extract when I run it for all the employees here (around 200) and for any significant length of time. It also seems very inefficient since it is repeating the same data over and over, and actually for anything other than the current loadings I only need the count of cases.

I've been trying to do it with data blending having the list of dates as a secondary data source but I'm having absolutely no luck with that.

I'm curious about doing something at the SQL level instead but I'm just a beginner with SQL so I have no idea where to go with that.

Yes, I fully expect the Cartesian join to generate a lot of records. That is why I recommended taking the "In Date Range" filter, and applying it to the extract, keeping when True, see step 3 of http://downloads.tableausoftware.com/quickstart/feature-guides/extracts.pdf for details on how to filter an extract. Then you will no longer need those filters on the worksheets that are checking the dates.